"Put a stop to" is an idiomatic expression that means to end or halt something. Antonyms for this phrase would be words or phrases that signify continuing, allowing or perpetuating something. Some examples of antonyms for "put a stop to" are "prolong", "extend", "allow", "encourage", "continue", "support" and "facilitate". These words have the opposite meaning of stopping or ending something. It's important to consider the context when choosing antonyms to "put a stop to" as they vary depending on the situation. However, regardless of the context, these antonyms convey an opposite meaning than the original phrase, implying that actions or behaviors should be continued rather than halted.